Table 1.

Examples of approved drugs with claimed anti-SARS-CoV-2 activity that are confounded by a very low (≤10) selectivity index

Hit candidate	EC50	CC50	Selectivity index	Drug class
2-deoxy-d-glucose	9.1 mM [12]	9.1 mM [12]	1	Hexokinase inhibitor
Amodiaquine dihydrochloride dihydrate,	4.9 μM [6]	34.4 μM [6]	7	Antimalarial
Amodiaquine hydrochloride	5.6 μM [6]	>38.6 μM [6]	>6.8	Antimalarial
Auranofin	1.4 μM [82]	5.7 μM [82]	4.1	Antirheumatic agent
Baloxavir acid	>100 μM [83]	85.9 μM [83]	<1	IAV Endonuclease inhibitor
Carmofur	24.3 μM [84]	133.4 μM [84]	5.5	Antineoplastic
Chloroquine	4.7 μM [62•] 46.8 μM [6] (phosphate)	>50 μM [62•,6] >100 μM [4••] 45 μM [32]	>10 [62•] >1 [6]	Antimalarial
	3.9 μM [4••] 30 μM [32]		>25.6 [4••]
			1.5 [32]
Chlorpromazine hydrochloride	4 μM [6]	11.9 μM [6] 48.9 μM [83]	2.9	Antipsychotic
	21.3 μM [83]
Cycloheximide	0.17 μM [12] 0.5 μM [NCATS OpenData Portal — SARS-CoV-2 cytopathic effect]	1.7 μM [ReFRAMEdb] 0.8 μM [NCATS OpenData Portal — SARS-CoV-2 cytopathic effect]	10 [ReFRAMEdb] 1.6 [NCATS OpenData Portal — SARS-CoV-2 cytopathic effect]	Protein synthesis inhibitor
Emetine	0.47 μM [12]	0.8 μM [ReFRAMEdb]	1.7	Protein synthesis inhibitor
Enisamium	1 mM [85]	10 mM [86]	10	Putative RNA polymerases inhibitor
Hydroxychloroquine	11.2 μM [6]	>50 μM [6]	>4.5	Antimalarial
Imatinib mesylate	5.3 μM [6] 4.9 μM [4••]	>30.7 μM [6] >37.3 μM [4••]	>5.8 [6] 7.6 [4••]	Tyrosine kinase inhibitor
Ivermectin	2.2 μM [60] 1.7 μM [62•]	2.2 μM [62•]	1−1.3	Anthelmintics
Lopinavir	26.6 μM [83]	49.75 μM [83]	1.9 [83]	HIV aspartic protease inhibitor
Mefloquine	8.1 μM [6]	18.5 μM [6]	2.3	Antimalarial
Nitazoxanide	1.0 μM [62•]	3.3 μM [62•]	3.3	Antiprotozoal
NMS873	25 nM [12]	25 nM [12]	1	ATPase inhibitor
Pladienolide	7 nM [12]	7 nM [12]	1	Spliceosome inhibitor
Quinacrine dihydrochloride	2.8 μM [4••]	22 μM [4••]	7.8	IMPDH inhibitor
Ribavirin	70 μM [12]	70 μM [12]	1	IMPDH inhibitor
Ritonavir	48.9 μM [83]	>100 μM [83]	>2 [83]	HIV aspartic protease inhibitor